OAKLAND — A 16-year-old boy, wounded in a March 9 gunbattle that claimed the life of a West Oakland mother trying to get her children to safety, was charged with murder Wednesday and will be prosecuted as an adult, authorities said.

Julian Ambrose Of Oakland is the seventh person to be charged in the killing of Chyemil Pierce, 30, who was shot in the head in the 2800 block of Chestnut Street. He was also charged with attempted murder because police believe he shot at Jerry Harbin Jr., another suspect charged in the case.

Ambrose was arrested Tuesday as he left Highland Hospital, where he had been undergoing treatment since the day of the shooting.

According to a probable cause for arrest statement made by Sgt. Michael Cardoza, Ambrose was found at the scene of the shooting suffering from multiple gunshots and was taken to Highland Hospital.

Cardoza said in the document that “witness statements and evidence located at the scene of the shooting indicates Ambrose was actively shooting and engaged in a gunfight which resulted in Pierce”s death.”

Authorities said Ambrose was one of several people in two groups of people who exchanged gunfire on the block.

One of those previously charged with murder and other crimes in the case, Anthony Sims, 19, a friend of Ambrose”s, was also wounded. He was also arrested after being treated for his wounds.

Others charged in the case are Alex Davis, 25, Dijon Ward, 20, Michael Stills, 21, Shelton McDaniels and Harbin, both 29. All have been charged with murder and other crimes except Ward, who is charged with being an accessory. Police believe he helped Sims flee the scene and conceal a weapon.

Those six are due in court May 18 for arraignment and are being held without bail, except for Ward whose bail is $80,000. Ambrose was scheduled to be arraigned Thursday.

The shooting happened after two groups of women got into a fight on Chestnut Street. After a man hit one of the women, Sims and Ambrose were phoned to come to the scene . The gunfight broke out soon afterward.

Pierce was hit in the head by a bullet as she screamed for her 7- and 9-year-old children to run to safety as the gun fight broke out. She was returning home after picking up the children from school. The mother of three children, Pierce worked in the human resources department of Kaiser Permanente.

Police have recovered several guns used in the shooting and said some of those involved have gang ties.